Malicious PDF — malware analysis report

Static analysis result for SHA-256 f53ed2a1ea5efc91…

MALICIOUS

PDF

78.1 KB Created: 2021-09-03 05:24:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-04
MD5: a488d893517a959f4ec234e434bee0f3 SHA-1: b0c835775ddbf3ba52f8c348af6694a6750bb89d SHA-256: f53ed2a1ea5efc91f39784d07ef0c5b5b372cc496853adc2686b0e28c1f59e3f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://queure.ru/uplcv?utm_term=bacteriuria+asintomatica+adultos+pdf PDF link annotation
    • http://snypes.nl/img/customer//files/buxajavaze.pdfIn PDF document text
    • https://strategieb2b.com/userfiles/file/52040719136.pdfIn PDF document text
    • http://zavalinka.by/var/upload/file/wodunakagonalupubikesuxu.pdfIn PDF document text
    • http://insfilings.com/skyzone_classic/upload/files/54055180249.pdfIn PDF document text
    • https://chauphongasia.com/wp-content/plugins/super-forms/uploads/php/files/t4pi9cgpcfq6kimbl984g0djrp/vivelezaru.pdfIn PDF document text
    • https://bursac.net/userfiles/file/30895603186.pdfIn PDF document text
    • https://tractorpulling-emmeloord.nl/upload/file/xujezuvekedaxidaruma.pdfIn PDF document text
    • http://capmar.eu/userfiles/file/80027855879.pdfIn PDF document text
    • https://movimientofamiliadejesus.com/images/uploaded/file/44519061901.pdfIn PDF document text
    • http://sahamit.net/userfiles/file/19384365824.pdfIn PDF document text
    • http://hosungtour.com/FileData/ckfinder/files/20210716_CED110981B0CBB2E.pdfIn PDF document text
    • http://securitydirect.it/wp-content/plugins/super-forms/uploads/php/files/202334d5111ea48db7c766d0cced4a37/jawomezejoji.pdfIn PDF document text
    • http://w-w.cn/isee/pfm/cms/uploadfile/fck/file/vilibe.pdfIn PDF document text
    • http://cck-brno.cz/ckfinder/userfiles/files/73974248008.pdfIn PDF document text
    • http://www.benvenutialmare.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d63779687e---40236556385.pdfIn PDF document text
    • https://institut-arabe.org/ckfinder/userfiles/files/12615874811.pdfIn PDF document text
    • https://alcc.vn/wp-content/plugins/super-forms/uploads/php/files/ucoppllh6osg0obb4gufvhkie5/sajezudarefutufuzu.pdfIn PDF document text
    • https://nanyangtextile.com/userfiles/file/bedepevufagibojigubaninod.pdfIn PDF document text
    • https://www.lorenzofranzone.it/wp-content/plugins/super-forms/uploads/php/files/e17a2d084d3abe25875654aedba50fa9/33173441088.pdfIn PDF document text
    • https://foundryindia.org/userfiles/file/23978800915.pdfIn PDF document text
    • https://evocative.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16075b8f03909f---94434902671.pdfIn PDF document text
    • https://best-of-geldanlagen.de/userfiles/file/91990032288.pdfIn PDF document text
    • http://halaljones.com/uploads/files/xakufus.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000cb37.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCB37 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e34e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE34E 10936 bytes
SHA-256: 1d526413d32e676751f6c0041c0aeebfd038e3f116b1a4fe7a90c50c9e4b4a86
font_02_sfnt_off0000fca2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFCA2 17152 bytes
SHA-256: f02a6ea7a1460648e9188ddac2c5623673c3f812ab0acd84eb69c550b6df4a71